Liquid treatment of sheets



10, 1967 D. L. GREENWOOD 3,

LIQUID TREATMENT OF SHEETS Filed June 1, 1966 5 Sheets-Sheet l Q N n Q N N 5:

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01 INVENTOR. "3 T; DAV/0 LGREENWQQD ATTORNEY Oct. 10, 1967 D. L. GREENWOOD 3,346,255

LIQUID TREATMENT OF SHEETS Filed June 1, 1966 3 Sheets-Sheet 2 INVENTOR.

,0 W0 4. 6' 11/14 000 fl S O 1967 D. L. GREENWOOD 3,346,255

' Filed June 1, 1966 LIQUID TREATMENT OF SHEETS 3 Sheets-Sheet 5 A59 F59. 4 //j l "I 6 INVENTOR. pa /0 4.6!?6'F/VWOO0 BY W S United States Patent Ofifice 3,346,255 LIQUID TREATMENT OF SHEETS David L. Greenwood, New York, N.Y., assignor to Varityper Corporation, Newark, N..l., a corporation of Delaware Filed June 1, 1966, Ser. No. 559,037 6 Claims. (Cl. 271-45) Prior to the invention of parent application Serial No. 373,815, a number of photographic film processing devices have been available in which rollers, belts, and other drive devices direct a film strip through various tanks and processes in properly timed relationship for development. Photographic film includes a base material which is unaffected by the solutions used for developing and fiXing the impression.

Certain duplicating methods, such as offset printing, make use of a master composition which is a combination of original art work, photographs, clippings from other articles and whatever other source material may be desired to compose a complete work. Then, an offset master is made by photographic methods. If necessary, the photographic negative is retouched to remove unwanted lines or other blemishes.

In the composition of such an original work, it is necessary to provide a great variety of type font and forms. One display piece, such as an advertisement page in a magazine, may mix bold type with italicized type, or the sizes and styles of type may need to be varied.

In order to provide the necessary headline or display type for these varied printing, duplicating or design applications, photocomposing machines are used in which the machine is equipped with .a permanent negative in the form of a durable plastic disc. These discs are instantly changeable, much like records in a phonograph. Then, the desired letter or other character is dialed into position to spell out any word or arrange any group of characters and an exposure light is actuated to print onto a silver halide paper stock very similar to that normally used in printing snapshot pictures. However, unlike snapshot pictures, the output from such photocomposing machines is often in long strips or sheets, varying often from eight to twenty inches.This paper web is processed in water solutions. In order to make the composing equipment practical .for routine oifice use, a means of development is required which does not require a darkroom. The art prior to this invention has attempted to use the various photographic film processors. However, by the time the paper is pushed from. one end of such device to a second bath wherein it is treated in a second solution, the compression strength of the web becomes virtually nil. Therefore, whenever the prior conventional devices used for photographing film are attempted to be pressed into service for use of the photocomposing machine development, generally the result is complete failure. The limp paper, when an effort is made to drive by means of pushing rollers, begins to buckle and fold in the machine and thereby spoils the printed stock for use in photocomposing.

Abstract of the invention This invention relates to liquid treatment of sheets and particularly to the handling of sheets which are inherently limp or which become limp during such treatment. First the discovery has been made that the limp sheet may be made to cling to a moving wall and thus be carried through the solution. The printing of such photocomposition paper requires the surface to be in full contact with the solution. To accomplish this result, and to maintain the equipment such that it can be quickly cleaned at the end of the business day, necessitates development in an inverted position. Those prior art devices which have belts driving film through a solution are directed to photograph- 3,346,255 Patented Oct. 10, 1967 ic processes which can remain in operation for considerable periods of time in commercial establishments, and generally provide a moving bed upon which the film may rest. Adapting such device to commercial office practice necessitates carrying the entire assembly to a disposal place because it is not possible to lift the driving belt out of the solution and take the solution away separately from the driving belt. This invention provides not only the concept of natural forces causing clinging of the paper to a moving wall for facile transport, but also provides proper orientation of parts in order that a developing solution tray may be separated from the moving wall, and the parts taken to a cleanup station with ease.

Developing equipment of various types for photographic film and paper are in common use, and these frequently operate on the basis of feeding the sheet from a pair of cooperating push rollers through a thin channel in a tank containing treating liquid, and into the nip of another pair of rollers which pull the sheet from the tank.

In certain instances, especially where the sheet being treated is paper, the sheet exhibits insuflicient stiffness to push properly through the tank and consequently collapses upon itself and forms a jam which stops the development procedure and destroys the sheet being treated. It is an object of the present invention to provide equipment which will obviate this difliculty.

According to the present invention the presently existing equipment is modified by arranging one wall of the channel so as to be moving in the same direction as that in which the sheet moves through the liquid, and at the same speed. It has been discovered that a limp sheet approaching this moving wall will exhibit an attraction phenomena and attach itself thereto, or at least its leading edge will receive a movement bias therefrom such that the limp sheet is led through the narrow channel without buckling or jamming.

In the preferred form of the invention this movable channel wall comprises a belt trained around the drive members, or a cylindrical drum, forming the convex mov ing wall of the channel.

The refinement of the invention is in the development of rollers, rather than a belt, in order to make possible a deep tank and a longer development path, but a tank which has a high ratio of fluid capacity to fluid requirements. By using closed displacement rollers, a small amount of fluid will be able to fill the resultant narrow channel between the rollers and tank walls.

It is an object of this invention, therefore, to provide a refined moving wall channel which also provides ease of tank transport.

Other objects, vfeatures and advantages will appear hereinafter as the description proceeds.

Description of the invention FIGURE 1 is a longitudinal section of a sheet treating device in accordance with the invention.

FIGURE 2 is a perspective view of the belt employed in the device of FIGURE 1.

FIGURE 3 is a top plan view, with parts broken away for interior illustration, of a refinement embodying the principles of this invention.

FIGURE 4 is a section taken on line 4-4 of FIG- URE 3.

FIGURE 5 is a diagram of gear drive arrangement employed for coordinating the feeding and moving wall.

FIGURE 6 is an illustration of the device with the moving wall assembly elevated out of the liquid holding tank.

FIGURE 7 is a diagrammatic illustration of the initial contact producing fold of the web material passing through the processing apparatus.

Referring to the drawing, the device relative to which the present invention is to be described, comprises a frame or base 11 which includes a pair of concave curved tank members 13 and 15, each preferably bearing guide ribs such as 17 and 19 on their surfaces. The tank member 13 is designed to hold a photographic-developer solution and tank member 15 is designed to hold a fixing or stabilizing solution, although it will be understood that these are not related to the invention in any way, and other types of liquid treatment are also contemplated.

Disposed above the tank 13 is a convex guide member 21 having ribs such as 25 and above tank member 15 a convex guide member 27. Each of these guide members forms with its cooperating tank member a thin channel through which the sheet is guided during treatment. These channels are designated A and B.

Push rollers 29, 31 introduce the sheet into channel A and push it through until it is grasped by a pair of transfer rollers 33, 35. These withdraw the sheet from channel A, drive it against a downwardly sloping guide 37 and into channel B, and then push the sheet through channel B. Finally, the leading edge of the sheet is grasped by pull-out rollers 39, 41 and withdrawn from channel B thereby.

The rollers 29, 31, 33, 35 and 39, 41 are all preferably driven at a constant speed from a conventional drive mechanism (not shown).

The structure described thus far is characteristic of known equipment which has been used for some time for the treatment of photographic film. It recently became important to use the same equipment for the treatment of both photographic film and photographic papers, and at this point difficulty was encountered. The photographic papers, apparently as a result of the liquid treatment in channel A, became so limp that they would not push reliably through channel B and frequently would collapse or buckle in channel B, thereby jamming the machine and destroying the sheet being treated.

It has been discovered that a very simple modification of the known device obviates the difficulty and makes the operation with limp sheets entirely practical. This change involves merely the substitution of a moving upper wall for channel B, which wall moves in the same direction as the sheet being treated.

Preferably this movable wall is provided by preparing a wide flexible belt of suitable material such as any flexible, tough, inert plastic material, and training the same around the convex upper guide member 23. Such a belt is shown in FIGURE 2 and is designated by reference character 43. In order to provide movement for the belt 43 it also is arranged to encompass roller 41 and to pass between it and roller 39 as shown in FIGURE 1.

Whenever a limp sheet is fed into channel B, for example a paper sheet which has received a preliminary liquid treatment in channel A, its leading edge is influenced by the movement of belt 43, perhaps becoming partially adhered thereto, and is dragged through channel B without any chance for stumbling or buckling. The

arrangement of the belt 43 about roller 41 also draws the leading end of the sheet directly into the nip of the pull-out rollers so that accurate guiding is achieved all the way.

It is conventional to have portions of the equipment removable for cleaning, inspection, and the like, and such an arrangement may be exemplified by considering that the convex guide member 23 is swingable upwardly about the axis of roller 41 to expose tank member 15. In order to facilitate this operation, belt 43 is preferably provided with a number of openings 45 which allow the liquid to drain rapidly from its upper surface and prevent the liquid from being trapped during the operation of raising guide 23 with consequent spilling.

The FIGURES 3 through 7 illustrate an embodiment which provides the moving wall concept, and in addition provides a structural and operator improvements which are desirable in certain uses. This modification, for example, provides deep tank trough sections, with displacement rollers rather than belts. The rollers displace a large quantity of fluid, and therefore the amount of fluid needed to fill the trough of the tank during operation will fall to a level far below the top level of the tank after the roller cylinders are removed. Hence, the tray is much more easily transported to a convenient disposal sink for disposing of the spent solutions and cleaning the apparatus. Other advantages will be apparent as the description of this modification proceeds.

The modified form is constructed upon a chassis which has a motor and control housing 111. A separate tank 112 sits upon the chassis bed and provides a first trough area 113 for the initial solution to which a web is exposed, and a second trough area 114 for another type of solution. It is the intent to drive a web through the first trough area and then strip as much of the chemical from the web as possible, and then direct the web into the second trough area for completion of the process. Therefore, the tank 112 has a division wall portion 116 where the two trough areas join, and this wall portion keeps the solutions separate from one another.

Two cylindrical drums 118 and 120 are each mounted for rotation in the tank 112, at least partially submerged below the level of the process liquid. The drums have smaller rollers which roll in surface contact on the drums to provide a drive of the web through the system. The drums and associated rollers are interlocked and driven by a series of gears and pinions. Two side plates and 126 are secured to a cover carriage 122 and provide hangers upon which the drums 118 and 120 are hung. The gears and pinions are located on the outside of plate 125, and the drums are between the plates. The group of drive gears and pinions are then adapted to mesh with a fixed position drive carried by the chassis 110 when the cover carriage is lowered.

Standards 128 are secured on the base of the chassis 110 and have slotted openings into which a pivot bar 129 carried by the cover 122 may fit. Thus, the cover carriage 122 may pivot from an open position as shown in FIG- URE 6 to a closed position as shown best in FIGURE 4, pivoting about the bar 129. However, the entire cover carriage and its burden may be lifted from the chassis by simply slipping the 'pivot bar 129 out of the slots in the standards 128.

Drum 118 is provided with an axle shaft 131, and the drum 120 with an axle shaft 132. Shafts 131 and 132 pass through the opposite side plates to mount and support the drums on the cover carriage. Thus, as the carriage is swung up to the position shown in FIGURE 6, the cylindrical drums are lifted out of the tank, and when the cover carriage is closed, the cylindrical drums are properly positioned for rotation within the tank.

A large gear 134 is mounted on shaft 131 on the outside of the plates 125, and large gear 135 is mounted on shaft 132 in like manner. A drive transfer shaft 137 is positioned to extend the side plates and carries a pinion 138 which meshes with the large gear 135. Spaced a distance from the pinion 138, on the same shaft 137, is a pinion 139. Pinion 13-9 is provided to mesh with a drive system which is indicated by the general reference character 140 in FIGURES 3 and 6. Thus, drive of pinion 139 will cause shaft 137 and gear 135 to rotate.

An idler pinion 141 is provided to bridge from pinion 138 to a pinion 142 which in turn is drivingly engaged on a roller shaft 143, and in mesh with large gear 135. Thus, drive rotation imparted to the pinion 139 will cause synchronized drive rotation of the two large gears 134 and 135, together with the coordinated drive of the shafts upon which the pinion gears 138 and 143 are secured.

Coupled with the synchronized drive of the cylindrical drums 118 and 120 in this manner, an intake roller 145 is carried by the side plates 125 and 126 for rotation against the surface of drum 118. A rubber belt 146 joins the shaft of the roller 143 and roller 145 to provide a resilient and yieldable urging of the two rollers toward one another. The varying mountings for rollers 143 and 145 are such as to allow a degree of free movement, and the resilient rubber belt 146 urges these two rollers towards one another against the surface of the roller 118.

Likewise, a roller 149 placed at the discharge side of the device in contact with the periphery of roller drum 120, is urged against the surface of that drum 120 by means of a resilient rubber belt 150 which encompasses the shaft of the roller 149 and the shaft 137. Thus, the entrance roller 145, the intermediate roller 143, and the exit roller 149 are rotated in synchronism with the surface of the respective cylindrical drums, and they are urged into tight contact with their respective drums.

A curved bottom guide composed of a plurality of wire members secured together is indicated by the reference character 152 in the trough area 113. A slot 153 in the top of the cover carriage 122 permits the entry of a web sheet into the apparatus in a direction such that the entering web will fall between the surfaces of the roller 145 and the cylindrical drum 118. The drive produced by the coordinated rolling of these two member will cause the web to move down into the confines of the narrow guide slot produced by the moving surface of the cylindrical drum 118 and the form of the curved bottom wire guide 152. Because the material being processed is relatively dry and fresh in this first exposure to developing solution, the force applied along the length of the web will be sufficient to feed the web through the closely confining guide slot and cause it to move down into the solution and up along the opposite side of the roller to be come engaged between the roller 143 and the surface of the drum 118. In this progress, the moving wall provided by the surface of the drum 118 aids the moving of the web.

A plurality of stripper guide plates 155, two of which are seen in FIGURE 3, and a side elevation seen in FIG- URE 4, have projecting portions which run in closely confining slots in the surfaces of the respective cylindrical drum 118 and 120. Hence, as the end of the web approaches the roller 143, the guide plates 155 cause the web in process to leave the surface of the drum 118 and double back over the top surface of the roller 143. As the web turns over roller 143, it is guided to project down into the second trough area 114. The stripper guide plates are hung on the side plates 125 and 126 by means of rods 156 and 158 which bridge across the two side plates.

The illustrated equipment is used to process photographic film as well as paper in order to enable one piece of equipment to satisfy all requirements. Film, however, has an anti-halation backing which must be exposed to the solution in the second tank free of the roller. Therefore, the second trough area 114 is made with one side more sloping than the other in order to produce an open area in which the web may progress before coming in contact with the roller 120.

A wire guide 159 provides a curved bottom guide for the material in the second trough area 114. Guide 159 has a receiving end extending up towards the axis of the roller 143, and will receive the lead end of the web as it comes over the top surface of the roller 143 under the guide of the stripper guide plates 155.

An intermediate portion of the curved bottom guide 159 extends downwardly from the receiving end to a lower position under the drum 120 and it is about at this location that the paper stock of the usual web material be comes entirely too limp to be further fed through the apparatus by means of the pushing force exerted by the roller 143 and drum 118. This observation has been made through a transparent end plate on the tank.

FIGURE 7 has been added to illustrate that which has been observed. The web, which is indicated by the reference character W in FIGURE 7, tends to curl against the guide 159, and begins to roll over upon itself. This action produces a movement of the web W toward the surface of the roller drum 120. A natural phenomena then takes place in that the paper stock, in its limp and wet condition, tends to grip the surface of the drum in preference to the liquid media in which it is semi-floating. Thereafter, although the extreme lead edge of the web W seldom, if ever, will pick up and join the surface of the drum 120, that which follows after the initial contact does do so with considerable tenacity. Hence, the web W is picked up by the moving upper wall of the channel which is defined by the guide 159 and the surface of the cylindrical drum 120, and is moved through a terminal portion 161 of the wire guide 159 and carried along substantially free of the guide until it reaches the exit roller 149. The curvature of the wire guide in the terminal portion 161 is substantially concentric with the surface of the drum 120 in or der that the action illustrated by the dotted lines in FIG- URE 7 be maintained as the web moves through the exit.

In actual practice, the thickness of the web of photographic paper employed for this purpose is about .0045". It has been found practical to space the wire guide 159 in the terminal portion 161 a distance greater than the thickness of the paper, because it is undesirable to place any surface too near the surface being developed, but a practical limit appears to be about eight times the thickness of the paper or about .036". Hence, this degree of space enables the curling tendency of the stock to push the stock against the surface of the drum 120 without allowing actual folding or buckling.

Whereas the present invention has been shown and described herein in what is conceived to be the best mode contemplated, it is recognized that departures may be made therefrom within the scope of the invention which is, therefore, not to be limited to the details disclosed herein, but is to be afiorded the full scope of the invention as hereinafter claimed.

What is claimed is:

1. Apparatus for conveying a web through a liquid treatment supported face down from the back surface thereof free of face surface contact, which liquid treatment renders the web progressively more limp as it proceeds from an entrance end of the apparatus to an exit end of the apparatus, said apparatus comprising:

a tank for holding process liquid;

a curved bottom guide having a receiving portion and a terminal portion, with an intermediate portion extending downwardly into said tank;

a moving belt means and means for guiding said belt means in spaced relationship to said bottom guide within said tank to define a substantially uninterrupted moving top wall extending across the operating width of the tank and serving as the top wall of a channel in which said guide is a stationary bottom configuration, said belt means and guide being spaced throughout to provide an unobstructed open channel, said channel having a greater depth than the thickness of the web of material beingprocessed, but less than sufiicient to allow the web of material to fold without first contacting said moving belt means.

2. Apparatus as defined in claim 1 in which there are pushing rollers adjacent the channel entrance for introducing the web of material into the channel, and pulling rollers adjacent the channel exit for grasping the leading edge of the web of material and pulling the web of material from the channel.

3. Apparatus for conveying a web through a liquid treatment supported face down from the back surface thereof free of face surface contact, which liquid treatment renders the web progressively more limp as it proceeds from an entrance end of the apparatus to an exit end of the apparatus, said apparatus comprising:

a tank for holding process liquid up to a predetermined operating level;

frame means, a cylinder drum having a bulk to displace a large quantity of liquid, said drum mounted on said frame means for rotation about an axis, said frame means having a first position placing said drum in said tank partially submerged below the level of process liquid, and a second position removed from the tank, a quantity of liquid in said tank up to said operating level with the cylinder in said first position being substantially below said operating level with said cylinder in said second position;

a curved bottom guide for said web of material; said guide having a receiving end and an exit end each positioned above said operating fluid level, an intermediate portion extending downwardly from said receiving end to a lower position under said drum, and a terminal portion extending upwardly from said lower position to said exit end with a curvature sub- 'stantially concentric to the drum, said bottom guide spaced from said drum a distance greater than the thickness of the material in process.

4. Apparatus for conveying a web of material through a liquid treatment as defined in claim 3, further characterized in that said cylinder drum is proportioned to displace a major portion of the tank volume.

5. Apparatus for conveying a web through a liquid treatment as defined in claim 3, further characterized in that said bottom guide receiving end and intermediate portion are spaced from said drum to provide exposure of a conveyed web on the top surface prior to reaching the said lower position.

6. Apparatus for conveying a web through a liquid treatment which renders the web progressively more limp as it proceeds, which apparatus comprises:

a tank for holding process fluid up to a predetermined operating fluid level, said tank having two adjacent separate trough areas;

two laterally spaced closed clyindrical drums mounted one in each said trough area for axial rotation at least partially submerged below said operating fluid level, said drum in each trough displacing a major portion of the available space in the said trough area to bring the fluid to said level;

in each trough, a curved bottom guide for said web, said guide having a receivng end and an exit end each positioned above said operating fluid level, an intermediate portion extending downwardly from said receiving end to a lower portion under said drum, and a terminal portion extending upwardly from said lower position to said exit end with a curvature substantially concentric to the drum, said bottom guide spaced from said drum in said terminal portion a distance greater than the thickness of the material in process;

in said first trough area, said curved bottom guide conforming to the shape of the drum therein substantially from said receiving end to said exit end;

in said second trough area, said bottom guide receiving end and intermediate portion being spaced from said drum to provide exposure of a conveyed web on the top surface prior to reaching the said lower positions;

an entrance roller drive means for feeding a web into the space between said first guide and said first roller;

an intermediate roller drive means positioned between said first and second trough areas for receiving a web from said first drum and feeding the web onto the receiving end of the guide in said second trough area; and

an exit roller drive means for receiving the web at the terminal exit and delivering the web from said apparatus.

References Cited UNITED STATES PATENTS 3,000,287 9/ 1961 Heldens. 3,062,122 11/1962 Smith et. al 15-100 X 3,092,006 6/ 1963 Limberger 89 3,287,013 11/1966 Fairbanks et al. 226-171 X FOREIGN PATENTS 1,276,429 10/1961 France. 1,020,866 12/ 1957 Germany. 1,096,201 12/1960 Germany.

768,621 2/1957 Great Britain.

555,146 1/1957 Italy.

M. HENSON WOOD JR., Primary Examiner.

J. N. ERLICH, Assistant Examiner. 

1. APPARATUS FOR CONVEYING A WEB THROUGH A LIQUID TREATMENT SUPPORTED FACE DOWN FROM THE BACK SURFACE THEREOF FREE OF FACE SURFACE CONTACT, WHICH LIQUID TREATMENT RENDERS THE WEB PROGRESSIVELY MORE LIMP AS IT PROCEEDS FROM AN ENTRANCE END OF THE APPARATUS TO AN EXIT END OF THE APPARATUS, SAID APPARATUS COMPRISING; A TANK FOR HOLDING PROCESS LIQUID; A CURVED BOTTOM GUIDE HAVING A RECEIVING PORTION AND A TERMINAL PORTION, WITH AN INTERMEDIATE PORTION EXTENDING DOWNWARDLY INTO SAID TANK; A MOVING BELT MEANS AND MEANS FOR GUIDING SAID BELT MEANS IN SPACED RELATIONSHIP TO SAID BOTTOM GUIDE WITHIN SAID TANK TO DEFINE A SUBSTANTIALLY UNINTERRUPTED MOVING TOP WALL EXTENDING ACROSS THE OPERATING WIDTH OF THE TANK AND SERVING AS THE TOP WALL OF A CHANNEL IN WHICH SAID GUIDE IS A STATIONARY BOTTOM CONFIGURATION, SAID BELT MEANS AND GUIDE BEING SPACED THROUGHOUT TO PROVIDE AN UNOBSTRUCTED OPEN CHANNEL, SAID CHANNEL HAVING A GREATER DEPTH THAN THE THICKNESS OF THE WEB OF MATERIAL BEING PROCESSED, BUT LESS THAN SUFFICIENT TO ALLOW THE WEB OF MATERIAL TO FOLD WITHOUT FIRST CONTACTING SAID MOVING BELT MEANS. 